Method of and to apparatus for use in concatenating fibrous material to form a spun yarn or strand



March 1, 1960 KEELER ETAL 2,926,483

METHOD OF AND TO APPARATUS FOR USE IN CONCATENATING FIBRQUS MATERIAL TO FORM A SPUN YARN OR STRAND Filed May '7, 1957 A 3 Sheets-Sheet l [avail/Z0215 lawramv M K949182- Wings 6. 60772 flwwx d. Fame w March 1, 1963 Ta KEELER ETAL 2,926,483

METHOD OF AND APPARATUS FOR USE CONCATENATING FIBROUS MATERIAL TO FORM A SPUN N OR STRAND Filed May '7, 1957 3 Sheets-Sheet 2 March 1, 1960 L. M. KEELER TA 2,926,483

METHOD OF AND TO APPARATUS FOR USE IN CONCATEZNATING gx xgRous MATERIAL TO FORM A SPUN YARN 0R STRAND 3 Sheets-Sheet 3 Filed May 7,

'zzm mozze jazareace J1: 2 692 JAY/75845 6 6awl9 3225 12! (I Ji AW V L I Lawrence M. Keeler, Whitinsville, Albert J. Vincent, Linwood, and James G. Gamble, Northbridge, Mass.; said Vincent and said Gamble assignors to said Keeler Application May 7, 1957, Serial No. 657,665 27 Claims. (Cl. 57-58.95)

This invention pertains to a novel method of and to apparatus for use in concatenating fibrous material to form a spun yarn or strand and, more particularly, to a method of and to apparatus such as to make possible the formation of a spun yarn or strand more expeditiously and with less damage to the individual fibers than is possible by the use of conventional spinning methods and/or apparatus. More specifically, the invention contemplates the use of a. gaseous medium, for example air, in associating the fibers to be spun.

Objects of the invention are 'to provide for spinning an even yarn by means which do not subject the fibers to damage from mechanical abrasion such as results from the employment of customary spinning devices. =A-further object is to provide for spinning a long staple fiber, for example, staple length rayon or other synthetic fibers, and to provide a yarn having as high a twist as may be 2 plane as Fig. 8, showing the controlling valve and associated parts with the valve in the open position; and,

Fig. 11 is a fragmentary vertical section showing a spinning head of slightly diiferent form from that shown in Fig. 8.

While in the drawings, but a single spinning unit is illustrated, it is to be understood that under commercial conditions, as many of these units as desired may be mounted, in suitable spaced relation, upon a frame simi lar to the conventional ring-spinning frame, and that, when so arranged, all of the units may be connected to a common exhaust trunk and to a suitable cable for supplying electrical current. I

Referring to the drawings and, in particular, to Figs. 1 to 7, inclusive, the character D indicates a set of backdrafting rolls of generally conventional type arranged to deliver the sliver S to the aprons A and A which, in turn, deliver the sliver into the nip of the top and bottom front rolls T and B, respectively. The bottom roll may be rubber covered. Preferably, the top front roll T is of the type shown in plan view in Fig. 2. This roll is of metal and has a helical peripheral rib R. ,A roll of this type reduces the fringe of stray fibers which are apt to be lost when drafting by conventional solid rolls, since the action of the ribbed roll is intermittent and by increments. The mode of operation of this helical ribbed roll is more fully described in the copending application,

desired. A further object is to provide means whereby the fibers, which constitute an untwisted strand, are drawn off by suction from the end of the strand and delivered pneumatically'into the spinning zone. A further object is to 'provide'means whereby a sliver of untwisted staple length fiber is reduced by drafting to the desired count and is then advanced into a vacuum nozzle which withdraws the fibers from'the advancing end of the untwisted strand or sliver and delivers them to spinning means. A further object is to provide means whereby staple length fibers are pneumatically presented to a spinning element rotating at a very high speed so as to provide free spinning ends which are caused to revolve by the spinning element and become twisted to form a spun yarn.

Other and further objects and advantages of the invention will be pointed out in thevfollowing more detailed description and by reference to the accompanying drawings wherein: Y

Fig. 1 is a diagrammatic side elevation with certain parts in vertical section, illustrating one embodiment of means for use in the practice of the invention;

Fig. 2 is a fragmentary diagrammatic plan view of a desirable type of high draft roll and associated parts for use in drafting the sliver preparatory to spinning;

Fig. 3. is a section von the line 3-3 of Fig. ,1, showing one form of spinning head or rotor;

Fig. 4 be fragmentary vertical section illustratinga modified form of spinning head or roto'r;

v Fig. 5 'is a fragmentary section on. theline 5-5 of Fig. 4; Fig. 6 is a fragmentary view, similar to Fig. 4, showing a further form of spinning heador rotor; Fig. 7 is ,a fragmentary sectionon the line 77 of Fig. 6;

Fig. 8 is a view, generally similar to "Fig. 1, illustrating a further modification;

Fig. 9 is a side elevation of the spinning head or rotor of Fig. 8 shown separately from the other parts;

Fig. 10- is a fragmentaryvertical section, in the same I Serial No. 657,961, filed May 8, 1957, now Patent No. 2,853,847.

A presser-rollQ cooperates with the front'bottom roll B to "grip the untwisted strand or sliver and to insure its delivery at a definite linear velocity such that the strand which emerges from between the. rolls .Q and B will be of the desired weight. M

- By way of example and assuming that the carded sliver S, where it enters the drafting rolls D, weighs 60 grains per yard, the drafting rolls may be driven at such relative speeds that the draft from the back rolls to the aprons A and A will reduce the 60-grain sliver to approximately 7 /2 grains per yard. The rolls T and B may then be set to provide a final reduction, for instance, to provide a total draft of 114.

The-drafted fibrous material, as it emerges from between :the rolls Q and B, enters the fiber inlet tube 10 which passes through the wall of thefixed cylindrical casing 11. This casing is provided with a closure 12 at its upper end and with an annular plug 13 at its lower end, the plug having a central aperture in which is fitted a bearing 14 for the shaft of an electrical motor M. The motor shaft is coaxial with the cylindrical casing 11 and projects up into the lower chamber 16 in the casing. A spinning head or rotor 17 is fixed to the upper end of the motor shaft. This spinning head or rotor is, as shown in Fig. 1, of generally spool shape, having the externally concave barrel portion 18 connecting end portions or heads of larger diameter than the barrel portion, the minimum diameter of the barrel portion being directly opposite to the inner end of the passage through the fiber inlet tube 10. This spinning head or rotor is hollow, having a central bore 21 (Fig. 3) and having diametrically opposed apertures 19 and 20 extending from the concave outer surface of the portion 18 into this central bore.

A stationary tube 22 is arranged in the upper part of the cylindrical casing 11 in coaxial relation with the rotor 17. This tube 22 is fixed in a central aperture in a septurn 23 secured within the cylindrical casing 11 with the lower end of the tube 22 disposed within the upper portion of the central bore 21 in the rotor 17. The bore 21 in the rotor is of such dimensions as to provide a slight clearance or air gap, for example of approximately of an inch between'the outer surface of the tube 22 and 3 the wall of the bore 21. The upper end of the tube 22 is seated in a counterbore in the cover member 12-the cover member having a central yarn delivery port 25 communicating with the interior of the tube 22. The tube 22 is provided with perforations 24 in that portion which is located between the parts 12 and 23. The upper chamber 26, into which these perforations open, is connected by means including a tube 27 with a suitable air pump (not shown) by means of which subatmospheric pressure is maintained within the upper chamber 26. With this arrangement, there is normally a constant strong .inflow of air into the open right-hand end of the fiber inlet tube 10. This incoming air enters l the lower or rotor chamber 16 and thence passes through the openings 19 and in the rotor and up into the tube 22 and thence out through the perforations 24 into the chamber 26 and thus to the suction tube 27. By arranging the openings 19 and 20 in the rotor at diametrically opposite points, the rotor is balanced, even though turning at a speed of from 10,000 to 12,000 r.p.m.

The apparatus is capable of spinning staple fiber of a substantial range of lengths. However, the distance from the nip of the rolls Q and B to the apertured surface of the rotor 17 should be slightly more than the length of the longest staple to be spun.

Assuming that fibers are being delivered continuously from between the rolls Q and B and that a suitable subatmospheric pressure is being maintained in the chamber 26,, the leading ends of the fibers, as they are delivered by the rolls Q and B, will enter the tube 10 through which a current of air is moving rapidly into the chamber '16. By the time the trailing end of a fiber is released from the grip of the rolls Q and B, its forward end is substantially in contact with the surface 18 of the rotor. The flow of air into the holes 19 and 20 in the rotor will carry the leading end of such fiber into one or the other of said holes. The surface speed of the rotor is substantially greater than the speed at which the fibers are advanced by the rolls Q and B; and, the surface speed of the rotor is also greater than the velocity of the air stream which passes through the tube 10. At the instant of contact by the leading end of the fiber and the rotor, the fiber speed is thus accelerated so that the trailing end of the fiber whips outwardly and contacts the inner surface of the cylindrical casing 11, it being noted that the advancing end of the fiber has already entered into the bore 21 of the rotor. If a pipe cleaner or similar device be pushed downwardly through the yarn delivery port 25 and through the tube 22 until its lower end is within the bore 21 of the rotor, the forward endof the fiber, which is within the rotor and which is turning rapidly with the rotor, will become twisted onto the stationary pipe cleaner. Since fibers are continuously being delivered into the tube 10, other fibers are following the same procedure as the first and their advancing ends will be caught on the pipe cleaner. If new the pipe cleaner be slowly withdrawn, the fibers will cling to it and will be twisted or spun together and other fibers, entering the rotor will twist onto the first ones, thus forming a continuous yarn. With each revolution of the rotor, one twist is introduced into the forming yarn-the twist point always remaining constant at the location indicated by the character P. If the first formed portion of the yarn be released from the pipe cleaner .and introduced between the take-up rolls 28 and 29, yarn will be formed and drawn off at a uniform and constant speed, thereby, in a single stage, forming a yarn Y from the untwisted fibers being delivered by the rolls Q .and B. During this operation, the fibers are under uniform conditions of control so that the yarn produced is uniform and equivalent to yarns formed of the same type of fiber by a conventional spinning means.

While a rotor, such as shown in Figs. 1 and 3, .having two diametrically opposite openings is desirable by reason of its balance so thatvit does not tend to vibrate when of the spinning units.

"escapes running at high velocity, it is possible to obtain desirable results, particularly at lower speeds, with an arrangement such as that shown in Fig. 4 in which the rotor has but a single aperture 19 in its forward wall. Such a rotor is useful in spinning longer staple fibers such as staple lengths of from two to three inches, it being understood that, as in the arrangement of Fig. 1, the distance between the nip of the delivery rolls (not shown) and the operative surface of the rotor should slightly exceed the length of the longest staple to be spun. Obviously, the spinning operation will be initiated by the use of a pipe cleaner or similar device in the same way as when using the device of Fig. 1. The rotor, having a single opening, appears to have some advantage as compared to that having the two openings since there is only one entrance for the air and thus there are no undesirable eddies of cross currents which might tend to disturb the untwisted free ends of the fibers, as may sometimes :be the case when the rotor has two openings. In the latter case, the trailing ends of long fibers may extend across one to the other of the openings and thus interfere with their continuous indraft into the proper opening. However, it is possible to spin longer staple fibers with the rotor having the two openings, if desired.

Figs. 6 and 7 each illustrate another form of rotor which is especially useful when spinning shorter staple fib'ersthat is to say, fiber of from of an inch to 1% inches of length. In this arrangement, the parts are generally similar to those shown in Figs. 1 and 4 except that the rotor 17 is in the form of a disk having three bent pins 30, 31 and 32 symmetrically arranged and pro jecting upwardly from the upper surface of the disk. These pins are located eccentrically to the axis of the motor-shaftand, as shown, each pin is preferably bent to a shallow V-shape with the apex of the V directed toward the axis of rotation. In this arrangement, as in that of Fig. '4, the perforated tube 22 of Fig. 1 is relaced by a short tube 22 which is fixed in the septum 23. As in the arrangement of Fig. 1, the nip of the delivery rolls will be spaced from the rotor a distance slightly exceeding the length of the longest staple to be spun. As shown in Fig. 6, this tube extends downwardly into thespace between the upper parts of the pins. With this arrangement, when first starting, it the advancing end of one fiber is carried by the air current into engagement .Withone of the pins 31, it is found that subsequent fibers will all contact the same pin.- As the advancing end of the fiber is drawn by the air current into the space between the pins and if a pipe cleaner be inserted so that its endis within this space, the advancing end of the fiber will be twisted onto the pipe cleaner and thus start the spinning operation .as described with respect to the apparatus of Fig. 1.

All of the devices shown in Figs. 1, 4 and 6, respectively, have been found to be effective for the spinning of viscose rayon of 1% inch staple, 1 /2 and 3 denier with a GO-grain sliver and from this sliver spinning 14s yarn at a spindle speed of from 10,000 to 12,000 r.p.m. Two-inch acetate rayon and .l /s-inch cotton have also been spun on the same apparatus.

In Figs. 8, 9 and 10, a further modification is illustrated in which like parts are designated by the same reference characters as those employed in Fig. 1.

, Thus, the apparatus comprises the back drafting rolls D, the aprons A and A,'the top' and bottom front rolls T and B and the presser roll Q.

J 'In this arrangement, the short cylindrical casing 11 has the lower head 13 provided with a central aperture,

and an upper head 12*which is formed by the lower member of the casing or housing of the motor M, the

vrnotor casing or housing being fixed to a support 33 which may be part of the frame which supports a series The upper member 35 of the motor casing or housing supports a second shortcylindrical member ll having a closure cap 12 m its upper end provided with the central'yarn delivery port 25 The motor shaft 34 is tubular, turning in suitable bearings L carried by the motor casing or housing and projects down with its lower end in the chamber 16 in the lower cylinder 11*. To the lower end of the tubular motor shaft, there is secured the spinning head or rotor 17 (as shown in Figs. 8 and 9). This rotor 17 is of a shape approximating the upper half of the spool-shaped rotor 17 of Fig. 1, but is devoid of the lower head of the latter, and its concave barrel portion is devoid of any side opening. At its lower end, this rotor 17 is provided with a hook-like member 37 at one side of a recess which terminates in an eye 38. The lower end of the rotor 17 is open. An upwardly tapering pin 39 is adjustably mounted in the central opening in the bottom head 13". The apex of this pin is coaxial with the rotorand within the latter and at a point slightly above the eye 38. l The tube 10 fixed in an opening of the wallin the cylinder 11*, has its outer end in position to receive the fibers delivered from between the rolls Q and B. The inner end of the tube 10 is directly opposite tothe rotor 17*. As in the device of Fig. 1, the distance between the nip of the drafting rolls and the peripheral surface of the lower end of the rotor 17 should slightly exceed the length of the longest staple to be spun. A chamber 26 in the upper cylinder 11* opens into a short tube 27 which leads to a trunk 36 designed to extend along a series of spinning devices such as that shown in Fig. 8, for example mounting on a frame similar to the conventional ring-spinning frame. The trunk 36 leads to a vacuum pump or the like such as to maintain sub-atmospheric pressurein the chamber 2.6 of each of the spinning devices. I I A feeler arm 40, pivoted at 43 to a suitable support, has a free end which normally rests upon the yarn Y which is formed by the spinning apparatus and which is being delivered to the traverse drum 41 on which rests the take-up package 42 whichis driven by frictional contact with drum 41. Should the yarn break during the operation, the arm 40 will drop and a short arm 44, secured to the arm 40, will contact the actuating pin 45 of a micr-o-switch 46 thereby closing an electrical circuit through a solenoid 47. This solenoid has a core 48 to Which is pivotally secured the lower end of a lever arm 49 connected at its upper end to a rotary, tubular valve member 48 which is housed in a cylindrical casing 49. The casing may extend along a series of the spinning units and is connected to a vacuum pump, or the like, so that the interior of the casing is at sub-atmospheric pressure. The casing has an upwardly directed suction nozzle 51 which is disposed, as shown in Fig. 8, just to the right of the inlet end of the tube 10 The valve 48 is provided with a port 50 in its side wall which may, at times, as shown in Fig. 10, be brought into registry with the lower end of the nozzle 51. of the solenoid in the position shown in Fig. 8; but, upon breakage of the yarn Y and the energizing of the solenoid, the core 48 is moved to the left- (Fig. 8), thus turning the valve 48 until its port 50 is registered with the nozzle 51. When so positioned, air is drawn down into the nozzle 51 more rapidly thaninto tube 10 so that fiber will no longer be drawn into the rotor and, thus, jamming of the spinning apparatus by the accumulationof fiber within the rotor is avoided. To start the apparatus again into operation, the arm 40 is swung upwardly, thus closing the valve 48, and a pipe cleaner is then again inserted down through the port 2S 'and, the operation is again initiated, after which the feeler arm 40 is restored to contact with the yarn.

In Fig. 11, a slight further modification is illustrated wherein the rotor 17 is of generally cylindrical shape; having a central bore which flares downwardly from a mid-point, and the inlet tube 1|) is arranged to deliver the fiber E into the lower part of the chamber 16 at a A spring 52 normally holds the core 48 point below the lower end of the .rotor. In this arrangement, a pin 39* is held in a central aperture in the lower closure member 13 0f the spinning device, the upper portion of this pin being slightly tapered, for example to have aninclined angle of approximately 5 while the extreme upper end of the pin is conical with a 60 included tip angle. The revolving rotor 17 causes air which enters the chamber 16 to whirl around the pin 39". In this device, as in that of Fig. 1, thedistance between the nip of the delivery rolls (not shown) and the peripheral surface of the pin 39 should slightlyexce ed the length of the longest staple to be spun. As the air moves upwardly into the central passage in the rotor, the fibers, entering through the inlet tube 10 loosely wrap around the pin 39 and slide up along the tapered portion of the pin. Projecting inwardly from the lower part .of the rotor, there are tufts 53 of brush bristles, each tuft, .for example, being of approximately the diameter of the tuft of bristles in a conventional tooth brush. Preferably, the tufts are arranged symmetrically about the axis of the rotor and there may be, for example, 8 tufts; although the exact number of such tufts is not material; As the fibers which loosely wrap around the tapered part of the pin 39 move upwardly, they are engaged by the bristles and caused to rotate at the same speed as the rotor. If a pipe cleaner be passed down through the hollow shaft 34, it will engage the fibers caught by the bristles and cause them to spin onto the pipe cleaner. When the latter is withdrawn, a free spinning end develops on the bristles so that new fibers entering through the inlet tube 10 are caught and the spinning of a yarn is initiated. Fibers cannot slide up and off of the pin because they are first engaged by the bristles, With this arrangement, the free ends of the fibers are under more and-better control than in the devices previously de scribed; and, it has been found in practice that this arrangement is to be preferred in the spinning of long staple fibers. I

For convenience in description, the rotor has, in each instance, been shown as turning about a vertical axis, and such terms as upper and lower have been used with respect to theillustrated arrangement, but with the understanding that these terms are not to be considered as, limitations upon the position in whichthe apparatus may be used or upon the interpretation of the claims.

While certain desirable embodiments of the invention have .herein been disclosed by way of example, it is to be understood that they invention is broadly inclusive of any and all modifications falling within the scope of the appended claims. i

. We claim:

1. That method of preparing spun yarn from staple length fiber which comprises as steps disposing the fibers in substantially parallel relation to form an untwisted strand, creating an air current, so advancing the strand as to deliver its forward end into said air current whereby the air current tends to detach individual fibers from the strand and to carry a detached fiber bodilyalong with it, guiding the air current to follow a path which is substantially perpendicular to the axis-of revolution. of a revolving part, so changing the course of said air current, as it nears said axis, as to cause it to move longitudinally of said axis, whereby the advancing ends of the fibres, suspended in and moving with saidair current, are constrainedto move in paths parallel to said axis, and, while the advancing ends of the fibres are so moving, causing the revolving part, by contact with the trailing ends of the fibres, to revolve said trailing ends about said axis while radially-spaced therefrom, whereby successive fibres are twisted together to form a spun yarn.

2. That method of preparing spun yarn from staple length fibres according to claim 1, wherein the spinning of the yarn is completed within said axially-moving air current, and as the spinning is completed,'the yarn is drawn oft along said axis of revolution whilethe air estates 7 current, now devoid of suspended fibres, is diverted laterally from said axis. r

3. Apparatus for use in preparing spun yarn from staple length fiber, said apparatus comprising means defining a cylindrical spinning chamber, a rotary shaft coaxial with said chamber and means for turning said shaft, a rotor carried by said shaft within the chamber, said rotor comprising an element which is eccentric to said axis,'means defininga fibre admission passage whose axis is perpendicular to the axis of the chamber and which opens into said chamber at approximatel the plane of rotation of said eccentric element of the rotor, a pair of constantly turning rolls operative to advance the end of a strand, consisting of unspun fibres, into said admission passage, the nip of said rolls being spaced from the path of revolution of said eccentric element of the rotor a distance slightly exceeding the length of the longest" staple to be spun, the chamber having, at one end, an axially located yarn delivery port spaced from the end oftherotrthe fibre admission passage being so arranged as to guide the air, entering the chamber through said admission port, to follow a path perpendicular to the axis of the rotor as it enters the chamber, means for withdrawing air from said chamber thereby to induce an in ward fiow of air through said fibre admission passage such as to detach fibres from the advancing end of the untwisted strand and to carry such detached fibres in suspension into said chamber, the rotor being sodesigned as to change the course of the air, as it nears the axis of rotation of the rotor, to cause it to move longitudinally of said axis toward the yarn delivery port, whereby the advancing ends of the fibres suspended in and moving with said air current are caused to move parallel to said axis, while the trailing ends of the fibres, by contact with said eccentrically located element of the rotor, are caused to revolve about the axis of rotation but radiall spaced from the latter.

4. Apparatus according to claim 3, wherein the rotor is a hollow part having an axial bore and a peripheral wall, the latter being provided with an opening through which the air current may enter said bore.

5. Apparatus, according to claim 4, wherein the bore in the rotor is open at its lower end.

6. Apparatus, according to claim 5, wherein the axis of the fiber admission passage intersects the axis of the rotor adjacent to the lower end of the latter.

-7. Apparatus, according to claim 4, wherein the bore in the rotor is open at its lower end and the lower portion of the rotor is provided with means operative, by engagement with the trailing ends of fibres whose forward ends are disposed within the bore in the rotor, to impart a motion of revolution to said trailing ends about the axis of the rotor.

8. Apparatus, according to claim '3, wherein the bore in the rotor is open at the lower end of the latter and a tapered pin, coaxial with the rotor, projects up into said bore.

9. Apparatus, according to claim 3, wherein the bore in the rotor is open at the lower end of the latter, said bore flaring in diameter toward its lower end, and stiffiy resilient fiber-impelling elements project from the wall of the tapering portion of the bore toward the axis of the latter.

'10. Apparatus, according to claim 3, wherein the bore of the rotor is open at its lower'end and 'fiares downwardly in diameter, a normally fixed pin coaxial with the rotor, having a conical upper end disposed within the bore of the rotor and a portion of approximately taper, immediately below the conical upper end, the axis of the fiber-admitting tube intersecting the axis of the rotor at a point between the upper and lower limits Of said tapering portion of the pin.

.11. Apparatus, according to claim 10, further characterized in having a plurality of tufts of bristles extending inwardlyfrom the wall of the tapering portion of the bore toward the axis of the bore.

1'2. Apparatus, according to claim 4, wherein the bore of the rotor is open at the lower end of the latter, the rotor having a downwardly tapering, concave peripheral outer surface and having a hook member at its lower end operative, by engagement with the trailing ends of fibres whose forward ends are disposed within the bore of the rotor, to impart a motion of revolution to said trailing ends about the axis of the rotor.

13. Apparatus for use in preparing spun yarn from staple length fibers, said apparatus comprising a hollow casing forming a support for an electric motor having a rotary shaft, a rotor within the casing and attached to the motor shaft to rotate with the latter, means dividing the interior of the easing into a plurality of chambers, the rotor being located in one of said chambers, means for withdrawing air from another of said chambers, means providing a yarn delivery port in the wall of the latter chamber, means providing communication between the chamber which contains the rotor and the chamber hat ing the yarn delivery port in its wall whereby sub-atmospheric pressure prevails in the rotor chamber, means providing a fiber inlet passage leading into the rotor cham-. ber, means for advancing the'end of an untwisted strand, consisting of fibers which are to be spun, into the fiber inlet passage through which a current of air is induced to flow by reason of the low pressure in the rotor chamher, the rotor comprising an eccentric element which revolves in a path coaxial with the axis of the rotor shaft but which is radially spaced from said axis, the fiber inlet passage being substantially perpendicular to the axis of the rotor shaft and having its delivery end located closely adjacent to the path of revolution of said eccentric element of the rotor, the parts being so constructed and arranged that, as the air current approaches the axis' of rotation of the rotor shaft, it is deflected to move longitudinally of said axis toward the yarn delivery port, whereby the leading ends of fibres suspended in the air current are caused to move in paths parallel to said axis, the eccentric element of the rotor being so arranged as, by contact with the trailing ends of the suspended fibres, to cause them to follow paths coaxial with said axis.

14. Apparatus, according to claim 13, wherein the rotor shaft is tubular, the bore in said shaft providing the communication between the aforesaid two chambers, an end closure from that chamber from which air is withdrawn, the yarn delivery port being in said end closure and coaxial with the rotor, and means operative to apply constant tension to the spun yarn thereby to draw it off uninterruptedly through said delivery port.

15. Apparatus,-according to claim 13, wherein the rotor is hollow and has an axial bore, the lower end of the bore in the rotor being closed and the rotor has an opening in its periphery through which the leading ends of fibers carried by the air current may enter the bore in the rotor.

16. Apparatus, according to claim 13, wherein the rotor is of approximately spool shape with a barrel portion whose outer surface is concave, the lower end of the bore in the rotor being closed and the barrel portion having at least one opening therein through which the advancing ends of fibers may be drawn by the air current into the bore in the rotor.

17. Apparatus, according to claim 13, wherein the untwisted strand is advanced into the fiber inlet passage by a pair of constantly turning rolls, the nip of said rolls spaced heads, the outer surface of the barrel portion being concave, the barrel portion having at least one opening in its wall, a pair of constantly turning rolls for advancing the untwisted strand into the fiber inlet passage, thenip of the rolls being spaced from the concave surface of the barrel portion of the rotor a distance slightly greater than the length or" fibers to be spun.

20. Apparatus for use in preparing spun yarn from staple length fibre, said apparatus comprising means defining a spinning chamber, means providing a fibre ad mission passage leading into said chamber, a pair of constantly rotating rolls operative to advance the end of a strand consisting of untwisted fibres into said fibre adcoaxial with the rotor and located above the upper end of the rotor, means for inducing an inward flow of air through the fibre admission passage such as to tend to detach fibres from the advancing end of the untwisted strand and to carry such detached fibres into contact with the rotor, the rotor comprising a disc coaxial with the rotor shaft, and at least one pin projecting upwardly from the disk and ecceutrically located with respect to the axis of the disk, the axis of the fiber inlet passage being so located as to intersect the geometrical surface defined by the pin as the disk rotates.

21. Apparatus, according to claim 20, wherein the rotor comprises a disk coaxial with and fixed to the rotor shaft, and a plurality of pins spaced symmetrically apart project upwardly from the disk, each pin being bent so that its axis forms a shallow V in a radial plane in the disk.

22. Apparatus, according to claim 13, wherein the motor has a housing which forms a closure for the lower end of the casing and a fixed septum divides the casing into upper and lower chambers, the septum having a central opening, anda tube fixed in said opening in the septum, the lower end of the tube entering the bore in the rotor, there being clearancebetween the tube and the wall of the bore.

23. Apparatus, according to claim 13, wherein the end of the casing and a cover, having a central yarn delivery port, closes the upper end of the casing, a fixed septum, having a central opening, dividing the easing into upper and lower chambers, the rotor being in the lower chamber, a tube fixed in the central opening in the septum, the lower end of the tube entering the upper part of the bore in the rotor, and the upper portion of the tube having perforations in its wall.

24. Apparatus, according to claim 13, including means automatically operative, while the rotor continues to rotate, low pressure is maintained in the rotor chamber, and fibre is continuously delivered to the fibre inlet passage, to prevent entry of fiber into the rotor chamber except when yarn is being drawn off in orderly fashion through the yarn delivery port.

25. Apparatus, according to claim 13, including a movable feeler which is normally held in elevated position by contact with spun yarn being drawn off through the yarn delivery port, and means operative in response to dropping of the feeler to terminate the delivery of fiber to the rotor.

26. Apparatus, according to claim 25, wherein the means for terminating the delivery of fiber to the rotor comprises a normally closed valve which is opened by the dropping of the feeler and thereby establishes an air current such as to divert fibers delivered from the untwisted strand away from the rotor.

27. Apparatus, according to claim 25, including valve means normally closing the entrance to a passage in which sub-atmospheric pressure is maintained, said entrance being closely adjacent to the entrance to the fiber admission passage, and a solenoid whose circuit is closed by the dropping of the feeler and which, thereby, opens the valve.

References Cited in the file of this patent UNITED STATES PATENTS 684,714 Phillips Oct. 15, 1901 778,604 Phillips et a1 Dec. 27, 1904 2,808,697 Williams Oct. 8, 1957 

